1. Field of the Invention
The present invention relates to heat sink assemblies, and particularly to a heat sink assembly having a fan embedded in a heat sink for providing forced ventilation.
2. Related Art
Developments in today""s highly information-intensive society have led to remarkable improvements in performances of electronic devices. During operation of many contemporary electronic devices such as central processing units (CPUs), large amounts of heat are produced. Such heat must be quickly removed from the electronic device, to prevent the device from becoming unstable or being damaged. Typically, a heat sink together with a fan is attached to an outer surface of the device to facilitate removal of heat therefrom.
The fan is often attached to a top side of the heat sink. Examples of this kind of heat sink assembly are disclosed in U.S. Pat. No. 6,304,445 B1 and Taiwan Patent No. 319404. A fan fixing frame is used to secure the fan to the heat sink. The frame constitutes an extra piece of equipment for the assembly, thereby increasing costs. In addition, the fan is disposed outside the heat sink, which increases an overall size of the assembly. This militates against the modem trend toward miniaturization of electronic equipment. Furthermore, in operation, the hottest part of the heat sink is generally its base, which is located distal from the fan. Airflow emanating from the fan is already weakened by the time it has reached the base of the heat sink. The position of the fan does not allow the base of the heat sink to fully benefit from the airflow generated by the fan.
An improved heat sink assembly with a fan, which overcomes the above-mentioned problems, is desired.
Accordingly, an object of the present invention is to provide a heat sink assembly having an embedded fan.
Another object of the present invention is to provide a heat sink assembly having a fan that facilitates significant cooling of a base of a heat sink.
To achieve the above-mentioned objects, a heat sink assembly of the present invention comprises a heat sink, a fan, and a retaining bar. The heat sink comprises a base, and a plurality of parallel fins extending upwardly from the base. The fins comprise a first outmost fin and a second outmost fin at opposite sides of the heat sink. The first outmost fin and intervening fins each define a longitudinal opening. All of the openings are aligned with each other, and cooperatively define a hexahedral chamber that is parallel with the base. The fan is received in the chamber. The retaining bar is secured to the first outmost fin by fasteners such as screws. A pressing portion is formed on the retaining bar, the pressing portion resiliently pressing one side wall of the fan. The fan is thus firmly retained in the chamber.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of preferred embodiments of the present invention with the attached drawings, in which: